1. Field of the Invention
The present invention relates to an organic light emitting diode (OLED) display and a method of manufacturing the same.
2. Description of the Related Art
An OLED used in a flat panel display includes an anode, a cathode and organic layers interposed between the anode and the cathode. The organic layers include a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL) and an electron injection layer (EIL) in addition to an emission layer. OLEDs are categorized into a polymer OLED and a low molecular weight OLED according to the composition of an organic layer, particularly, an emission layer.
To implement full colors, the organic layer needs to be patterned on a substrate. A shadow mask is used to pattern an organic layer of a low molecular weight OLED. An organic layer of a polymer OLED is patterned using inkjet printing or laser induced thermal imaging (LITI).
Unlike inkjet printing that is a wet process, LITI is a dry process which can finely pattern the organic layer.
A method of forming a polymer organic layer pattern using LITI requires at least a light source, an acceptor substrate and a donor substrate. The acceptor substrate is a display substrate on which an organic layer is formed and the donor substrate includes a transfer layer composed of a base film, a photothermal conversion layer and an organic layer.
Patterning of an organic layer on the acceptor substrate is performed in such a manner that the photothermal conversion layer absorbs a laser emitted from the light source and converts the laser into thermal energy, and the organic layer forming the transfer layer is transferred onto the acceptor substrate according to the thermal energy.
However, part of the organic layer that needs to be transferred to the display substrate using the laser may remain in the transfer layer during a transfer process.
The above information disclosed in this Background section is only for enhancement of an understanding of the background of the invention, and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.